The maintenance of gas turbine engines requires occasional removal of fuel nozzles from nozzle/manifold assemblies for inspection. In some engine designs this may require partial dismantlement of the engine, but even for those which have easily accessible nozzle/manifold assemblies, the task of removing and replacing nozzles is made cumbersome by the design of the assembly itself. For example, in order to remove a single nozzle it may be necessary to disconnect a number of spaced nozzle assemblies so that fuel lines are sufficiently flexible to permit withdrawal of the nozzle from the combustor.
U.S. Pat. No. 4,466,240 Miller discloses a fuel nozzle structure with external and internal removal capability. Referring to FIG. 1 of the patent, the nozzle support structure 35 is secured to a plenum-defining structure 12 (the structure 12 being referred to as a "combustor") which surrounds a combustion chamber 20. The nozzle 10 may be disconnected internally of the plenum-defining structure 12 by retracting bolts 64 which secure the nozzle to a fuel line 42. In addition to disconnecting the nozzle 10, this disconnects the fuel line 42 from the plenum-defining structure 12 (See col. 2, lines 64-66). When the nozzle 10 is replaced, the fuel line 42 must be repositioned for securement by the bolts 64. Conversely, the nozzle 10 may be disconnected externally of the structure 12 by retracting bolts 34. This requires that the entire nozzle support structure 35 and fuel line 42 be separated from the structure 12.
Since fuel nozzles are a high-maintenance item in comparison to manifolds, it is desirable to remove nozzles without having to separate fuel conduits or other portions of the manifold from the structure to which the manifold is secured. This result can be achieved by use of the present invention.
An objective of the present invention is to provide greater facility in the maintenance of gas turbine engines.